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gleitet' tant lstut @hun ROBERT W. SMITH, OF TIPPECANOE, OHIO.

Letters Patent 1Y0. 66,900, dated July 16, 1867.

IMPROVEMENT IN BRIDGES.

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T0 .ALL WHOM I'I MAY CONCERN:

Be it known that LROBERT W. SMITH, of Tippecanoe city, in the county ofMiami, and State of Ohio, have invented a new and useful Improvement inBridges; and I do hereby declare that the following is a full,

clear, and exact description of` the same, reference being had to theannexed drawings, making part of this specification, in which- Figure 1is a vertical longitudinal section.

Figure 2 is a horizontal section oi' one side on the line :z: fr.

The same letters are employed in both figures in the indica-tion ofidentical parts.

A is the sill, which in the case represented is composed of threeparallel dat pieces of timber, laid near to but not iircontactwith oneanother. This number is, however, not absolute. B is the chord,similarly constructed, but it may be made of lighter pieces C C are theposts. The end posts Cl are vertical, as also the two central posts C2;all the others marked C are inclined on euch side upwards from thecentre towards the respective ends. They are attached above and below tothe sill and chord-pieces by bolts passing from side to side through theWhole; When the sills and chords are composed of more than two piecesthe posts are placed alternately on each side of the middle timber. Theposts are framed into the sills and chords by cutting partly from each.The braces D 'D are set diagonally between the opposite faces oi' theposts C C, reaching from one post at the top to the base of the secondpost, in succession. The end braces rest against the base of thevertical posts O1, and these, near the middle, are set into a notch cutin the vertical middle posts C2. The braces Dl are placed on each sideof the centre pos-ts their feet resting against the posts C. Thesebraces D between the inclined posts D are not framed into the posts, butrest squarely against the posts at the top and bottom, the angle onlytouching the sills and chords. Cl I)2 are braces from the buse of theend posts, framed into the side ot' the post U near the top. E and E arethe upper and lower cross-ties, on one or the other of which the door ofthe bridge is laid. The bridge represented isknown as a double-trussbridge, as there are two sets of posts and braces. Bridges may be madewith `a single truss, or with three or more, depending upon the strengthrequired.

The advantages claimed for this bridge are its strength, owing to theequal distribution of the load; its staunchness following from the modeof bracing; and its lightness and cheapness. All iron supporting andbracerods, and also the cast-iron triangular foot-pieces in common use,are dispensed'with.

What I claim as my invention, and desire to secure by Letters Patent, is

1. The bridge constructed with inclined posts C C, in combination withthe braces-D D, resting equally against the sides of the posts, andarranged in relation to the sills and chords, substantially asdescribed.

2. In combination wit-h the inclined posts and braces, as described, Iclaim the vertical central posts C2, and braces D, substantially asdescribed.

R. W. SMITH. [L s] Witnesses JNO. T. WOODWARD, C. F. Bowen.

